Method of producing boards



March 13, 1951 o. H. ORNER I 2,544,935

METHOD OF PRODUCING BOARDS Filed March 15, 1946 l/u "(William)" mmmxm I O-rro HmeA O'ZNEQ IAIVENTQR,

Patented Mar. 13, 951

ENT I o'FFlcE 1 METHOD or PRODUCING. noAnns Otto Harald firner, Hudiksvall, Sweden Application March 13, 1946, Serial No. 654,143

' In Sweden March 17, 1945 3Clain1s. (Cl. 1411-309) It is known that the coefficient of shrinkage of all kinds of wood is the least at right angles to the annual rings. Timber which has been prepared in such manner that the annual rings will be standing between the cutting surfaces is therefore used in joinery in such cases where the product shall have the least possible mobility. To restrict such mobility and to impart stability to the material, where such stability is required, for instance in doors and. so forth, it is common practice to apply turned counter veneer of a thickness of 2-3 mm. Since such veneer has the greatest mobility of the species of wood in consideration, and may even vary greatly when taken from one and the same trunk, this material leads to appreciable tensions on both sides of the board, which tensions may thus be different on the opposed sides.

The present invention has for its object to produce boards permitting of being used, for instance, for blind wood as well as for counter veneer, so that the least possible movement is obtained in the plane of a slab produced from said boards, and the method in consideration is principally distinguished by the features that sectors taken out of logs are sawn into blanks tangentially to theannual rings, that the blanks are arranged in flakes of uniform thickness, which are placed on top of each other and glued together into a block having the annual rings of the blanks running in the same direction, and that the boards are sawn out from the block transversely over the annual rings along the fibres.

The invention also refers to boards, such as so-called lamella boards, produced in accordance with this method.

The accompanying drawing illustrates various working steps in the performing of the method. Fig. 1 shows the sawing of a log into sectors by Way of diagrammatic representation, and also shows how these sectors are sawn into blanks. Fig. 2 shows a block composed of the sawn blanks, and Fig. 3 shows a lamella board, in which the veneer and the blind wood have been produced from boards according to the invention, said lamella slab being slitted in part.

In sectors 2, which have been sawn out of the log 3 with the center of a circle in the core, the total tangential shrinkage is greatest in the peripheral portion and diminishes toward the core, but the shrinkage is the same at diflerent points of the radial cuts. Consequently, if blanks 4 be sawn tangentially to the annual rings in such sectors, the tangential shrinkages will be 2 mutually proportional in the various blanks, by reason of which blocks glued together from these blanks, Fig. 2, are not distorted when swelling or shrinking. In blocks which are glued together from blanks 4 taken out of sectors 2 of 45, said blanks being alternately placed in flakes in such manner that the annual rings of adjacent blanks are curved in opposite directions, no mutual succession need therefore be observed between the blanks, the various flakes permitting of being composed from blanks taken from any part of the sector. These diiferent flakes will practically have equivalent tangential coefiicients of shrinkage, and boards, which are sawn from blocks to the desired thicknessescompare the chaindotted lines AA and 3-13 in Fig. 2.-will show transverse annual rings between the cutting surfaces. Where these boards are used, for instance for blind wood, the same consequently answer the technical demands for the least possible tendency toward movement in the plane of the slab and for the least possible tendency toward distortion at right angles to the plane of the slab. In the lamella slab shown in Fig. 3, the blind wood 5 and the counter veneer B are both made from boards according to the invention.

The use of the boards is not restricted to lamella slabs.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A method of producing boards, wherein sectors are physically removed from logs and are then sawn into a series of blanks tangentially to the annual rings, said series of blanks extending substantially to the apex of the sector, said blanks being arranged in flakes of a uniform thickness, placing said blanks on top of each other and gluing the same into a block with the annual rings of the blanks extending in the same direction, said boards being sawn from the blocks in a transverse direction to the annual rings along the fibres.

2. A method of producing boards, wherein sectors at an angle of 45 are physically removed from logs and are'then sawn into a series of blanks tangentially to the annual rings, said series of blanks extending substantially to the apex of the sector, said blanks being arranged in flakes of a uniform thickness, placing said blanks on top of each other and gluing the same into a block with the annual rings of the blanks extending in the same direction, said boards being sawn from the blocks in a transverse direction to the annual rings along the fibres.

3. A method of producing boards, wherein sectors at an angle of 45 are physically removed from logs and are then sawn into a series of blanks inside the log segment within said angle tangentially to the annual rings, said series of 5 blanks extending substantially to the apex of the sector, said blanks being arranged with their inclined edges located against each other so that every second board has its broadest side turned upwards and every alternate second board has its narrowest side turned upwards, said blanks being arranged in flakes of a uniform thickness, plac ing said blanks on top of each other and gluing the same into a block with the annual rings of the blanks extending in the same direction, said boards being sawn from the blocks in a transverse direction to the annual rings along the fibres.

o'r'ro HARALD CSRNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 301,068 Parmelee June 24, 1884 2,316,111 Stamm Apr. 6, 1943 FOREIGN PATENTS Number Country Date 15,059 Great Britain Aug. 9, 1895 291,113 Great Britain Nov. 8, 1928 

